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131.
The water wars rationale predicts that countries will wage war to safeguard their access to water resources, especially if there is water scarcity, competitive use and the countries are enemies due to a wider conflict. Following this argument, India and Pakistan should have fought a war over the Indus basin instead of negotiating the 1960 Indus Waters Treaty. In explaining this Indo–Pakistan cooperation which is specifically over water, the critical feature that emerges is that through cooperation the countries were able to safeguard their long–term water supply. In other words, cooperation is water rational. Using the Indus basin experience, the underlying logic of the water wars rationale is questioned, in particular, the use of public statements by key decisionmakers as evidence of future water wars and is shown to be wanting.  相似文献   
132.
Environmental impact assessment (EIA) of any project is essential for understanding the sustainability of the project. For sustainable development of hill tracts, electricity is inseparable. Like other parts of Bangladesh hill tracts districts felt increasing demand of electricity. In this paper an attempt has been taken to present the existing environmental condition and analysis the future environmental condition after implementation of project. Electrification will extend the length of the active day. Electrification will improve security (people’s perception of safety and security) at the region. The elements of the project identified as components for analysis are chosen based on DOE’s guideline. The study showed that 87% people say that they feel safer at night since being electrified. Impacts are classified on the basis of EPA’s scaling and DOE, university’s teachers, NGOs expert’s opinions. Value more than 10 is classified significantly affected element of the project. In this paper advantages and disadvantages of the Electrification Project has been presented.  相似文献   
133.
Urbanization is an inevitable phenomena for the country like Bangladesh. The push and pull factors help to migrate people from rural area to urban area. As a result haphazard and unplanned urbanization create environmental degradation. Survey data reveals that inadequate solid waste disposal services, lack of adequate public water supply, traffic congestion, water logging, air pollution, noise pollution, hill cutting are the main problems in the city area. Concentration of dust as well as SOx, NOx exceeded the allowable limit at the selected points. Groundwater level of Sylhet city has a considerable lowering over the last few decades. It has lowered from 3380 mm below ground in 1982 to 7880 mm below ground. Sylhet is located in highly seismic risk zone but most of the buildings and other structures in this area are constructed without considering earthquake risk. Environmental degradation index was calculated based on economical condition of the country.  相似文献   
134.
Natural Hazards - Disaster risk perception and risk appraisal are essential in formulating an appropriate disaster risk reduction policy. This study examines the actual vs perceived drought risks...  相似文献   
135.
Natural Hazards - Bangladesh is one of the world’s most climate-vulnerable countries. The appraisal of household vulnerability and capacity to adapt under climate change is therefore crucial...  相似文献   
136.
The sandstones of the Ridge and Athleta members of Chari Formation (Callovian-Oxfordian) exposed at Jara have been analyzed for their petrographical and geochemical studies. Texturally, these sandstones are medium to coarse grained, poorly to well sorted, sub-angular to sub-rounded, and show low to medium sphericity. These sandstones were derived from a mixed provenance including granites, granite-gneisses, low and high-grade metamorphic, and some basic rocks of Aravalli range and Nagarparkar massif. The petrofacies analysis reveals that these sandstones belong to the continental block and recycled orogen tectonic regime. The studied sandstones are modified by paleoclimate, distance of transport, and diagenesis. Mineralogically and geochemically, sandstones are classified as quartzarenite, subarkose, arkose, sublithic arenite, and wacke, respectively. The A-CN-K ternary plot and CIA, CIW, PIA, and ICV values suggest that the similar source rocks suffered moderate to high chemical weathering under a hot-humid climate in an acidic environment with higher \({\text{P}}_{{{\text{CO}}_{ 2} }}\). Generally good to strong correlations between Al2O3 and other oxides in these sediments indicate clay mineral control. The K2O/Na2O versus SiO2 diagram indicates that the studied samples occupy passive margin fields but the SiO2/Al2O3 versus K2O/Na2O plot suggests that the Athleta Sandstone and Ridge Sandstone fall within the passive margin field, while Ridge Shale falls within the active continental margin field.  相似文献   
137.
Oceanic Islands in the Pacific and Indian Oceans have extremely small land areas, usually less than 500 km2, with maximum height about 4 m above sea level. The Republic of Maldives is an independent island nation in the Indian Ocean south of Sri Lanka which stretches vertically in the Indian Ocean from 07° 06'N - 0° 42'S. The land area of this island country is about 300 km2, and none of Maldives' 1190 islands has an elevation more than 3 m above sea level. In fact the Maldives has the distinction of being the flattest country on earth, making it extremely vulnerable to the effects of global warming. Of the south Asian countries, the Maldives is the most vulnerable nation, facing severe consequences as a result of global warming and sea level rise (SLR). Because of their obvious vulnerability to SLR, the Government of Maldives is very much concerned about climate change. As global warming and the related SLR is an important integrated environmental issue, the need of the hour is to monitor and assess these changes. The present article deals mainly with the analysis of the tidal and Sea Surface Temperature (SST) data observed at Male and Gan stations along the Maldives coast in the northern and southern hemispheres, respectively. The objective of the analysis is to study the trends of these parameters. Trend analysis is also performed on the corresponding air temperature data of both stations. The results show that Maldives coastal sea level is rising in the same way (rising trend) as the global sea level. The mean tidal level at Male has shown an increasing trend of about 4.1 mm/year.Similarly at Gan, near the equator,it has registered a positive trend of about 3.9 mm/year.Sea level variations are the manifestations of various changes that are taking place in the Ocean-Atmosphere system. Therefore, the variations in SST and air temperature are intimately linked to sea level rise. It is found that SST and air temperature have also registered an increasing trend at both stations. The evidence of rising trends suggest that careful future monitoring of these parameters is very much required. Tropical cyclones normally do not affect the Maldives coast. However, due to its isolated location, the long fetches in association with swells generated by storms, that originated in the far south have resulted in flooding. Thus the rising rate of sea level with high waves and flat topography have increased the risk of flooding and increased the rate of erosion and alteration of beaches.  相似文献   
138.
The present research deals with the geochemical characteristics of the Holocene sediments from Alamdanga area, Chuadanga district, Bangladesh. Main goals of the study are to delineate source rock characteristics, degree of chemical weathering and sorting processes and behavior of redox conditions during deposition of the sediments. Geochemical characteristics of the sediments show comparatively a wide variation in accordance with stratigraphy in their major element contents (e.g. SiO2 69.46-82.13, A1203 2.28-8.88 in wt%), reflecting the distinctive provenance and in part an unstable period in terms of tectonic activity. Geochemical classification of the sediments shows mostly sub-arkose with few sub-litharenites. Some major and trace elements display comprehensible correlation with A1203 confirming their possible hydraulic fraetionation. The chemical index of alteration (CIA*), W* index, index of compositional variability (ICV), plagioclase index of alteration (PIA*) values and the ratio of SIO2/Al2O3, suggest low degrees of chemical weathering in the source areas as well as immature to moderately mature the sediments. The sediments suggest semi-arid climatic trends within oxic deltaic depositional conditions during the Holocene, at 3-12 ka. Whole rock geochemistry and discrimination diagrams demonstrate the continental signature derivatives, which might have been derived from the felsic to intermediate igneous rocks (granitic plutonic rocks) as well as from quartzose sedimentary/metamorphic provenance. These typical sources are present in a vast region of the Himalayan belt and catchment areas of Ganges. The tectonic setting of the sediments demarcates typically passive margin with slightly continental arc system.  相似文献   
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